Patent GB-602040-A (GB)
Title: Improvements in or relating to floating bridges
IPC: E01D15/14
Filed: 1945-10-11
Abstract: 602,040. Floating bridges. GILES, H. L. Oct. 11, 1945, No. 26652. [Class 20(i)] Relates to floating bridges for use with non-tidal waters and where there is little or no current, and consists in an assemblage of self-buoyant unit bays interconnected end to end and having hinged flexible side flaps which, when the unit bays are depressed under load, are correspondingly elevated, so providing the requisite buoyancy for the load and also preventing the ingress of water. Each unit bay, Fig. 3, comprises a rigid rectangular framework constructed of three roadbearers 1, Fig. 11, interconnected by eight transoms, the ends of which are adapted to fit the brackets 6 on the roadbearers, and eight longitudinal chesses 13. The chesses 13 are positioned by four button transoms 2, the other four transoms 3 being plain. The framework has a mat-like waterproof covering 14 which projects substantially horizontally from opposite sides and is supported at these places by a series of parallel float-arms 29 individually hinged to the framework so as to be capable of rocking movement in the vertical direction. A timber sealing batten 16, Fig. 9, with hinged ends 17 is placed on top of the mat 14 over the centre roadbearer, slots 18 being provided for the buttons 15 which protrude through holes in the mat. Outer sealing battens 19, Fig. 10, with hinged ends 20 are placed on top of the mat over the outer roadbearers. The decking consists of fourteen chesses 23 laid transversely over the sealing battens, located by the buttons 22 on the outer sealing battens, and projecting alternatively from opposite sides so as partly to overlie the projecting portion of the mat and so limit the upward rocking movement of the float arms 29. The float arms 29 are of timber and have steel hooks on their ends which are hooked into the brackets 30 on the battens 19. Rope lashings 31 attached to the mat 14, are passed through a fork 32 at the outer end of each float arm and secured to cleats 33 thereon. Rope loops 27, formed by ropes passing through tucked canvas strips 28 stitched to the mat 14, are slipped over the projecting ends of the chesses 13. A centre riband 24 and outer ribands 25, of timber, are laid over the chesses 23 and above the corresponding roadbearers, to which they are secured by bolts 26 with claw-like heads which engage in slots 15A in the sides of the roadbearer buttons 15. The coupling means between the ends of the unit bays comprise the male and female connectors 4, 5 on the ends of the roadbearers 1. A pair of hooks 36 in the connector 4 embrace a pin 37 in the connector 5 on the end of the corresponding roadbearer in the adjacent unit bay. Alternative movement-limiting means are provided, comprising either a pin 38 passing through the slots 39 in the connector 5 and through holes in the connector 4, or a bolt inserted through the holes 43 in the connector 5 and through the slots 44 in the connector 4, the latter arrangement permitting greater articulation, at the coupling between the unit bays, than the former. The ends of the mat 14 are slit at 45 to form a central flap 46 flanked by side flaps 47. The central flaps 46 of adjoining unit bays overlap and are held in place by the end chesses 23. This overlapping is allowed by the hinged ends 17 and 20 of the sealing battens. A watertight joint is made between the side flaps 47 of adjoining unit bays by the method disclosed in Specification 594,943, [Group VIII]. Ramps, Fig; 16, are attached to the end bays, and comprise three wedge-shaped bearers 53 hinged to a junction chess 54 to the underside of which are fitted three brackets 55 connected to the respective roadbearers 1. Three panel units 56, each consisting of three chesses 57 screwed to three ribands 58, are secured to the bearers 53. The end of the ramp is fitted with shackles 61 to which drag or anchor ropes 62 can be attached. The central flap 46 of the mat 14 of the end bay is doubled back on itself and clamped between the end chesses 23, and the side flaps 47 are secured by a lashing 63. To keep the framework of a unit bay square during erection tie-rods 11 with turned-down ends are fitted diagonally between the lugs 12 on the sides of the roadbearers. Each unit bay has a pair of timber guide posts 34, one of which is shown in Fig. 3.